This image released by the Royal Thai Police on Wednesday, August 19, 2015, shows a detailed sketch of the main suspect in a bombing that killed a number of people at the Erawan shrine in downtown Bangkok, on Monday.
Police officials told reporters Thursday that authorities believed those behind the blast must have planned it in advance, maybe a month ahead of time, and would have needed a site inspection team, bomb makers, bombers and an escape team.
Another police spokesman said that the main suspect – who police desbribed as a tall, fair-skinned foreigner speaking neither Thai nor English – may have left the country, but that police were “unsure” of his whereabouts.
Police also said they would take the sketch to a court and ask that an arrest warrant be issued for a man matching the description.
“The bombing suspect could probably be killed if he does not surrender”.
Investigators suspect that two other men seen on the grainy video footage are his accomplices.
Police chief Somyot Poompanmoung said on Wednesday that the attacker did not carry out Monday’s attack by himself, without elaborating further.
A man who left a backpack at the scene of Monday’s deadly bombing in central Bangkok is now the focus of the hunt for the bomber, said police.
“I am confident that there are Thais involved but I am not saying it is just Thais or that there are foreigners”, he said.
The shrine is dedicated to the Hindu god Brahma, but it is also popular with Buddhists and attracts many visitors from east Asia, as well as local Thais.
Police say two other suspects were also identified in CCTV footage of the blast site.
“He had white skin and must have been a European or have mixed blood, perhaps with Middle Eastern blood”, said police spokesman Prawut Thawornsiri.
On Thursday Thai Prime Minister Prayut Chan-O-Cha said he would not attend a memorial service for the victims at the shrine on Friday because of growing fears for his life.
Thailand’s military leadership has declared the attack was unlikely to be the work of foreign militants and that it was not targeted at China, despite the shrine being popular with Chinese tourists.
“If citizens or anyone can give us information or clues that lead to the arrest of this man, I have set a reward of 1 million baht”, Somyot said.
Speaking in a television address on Tuesday evening, Mr Prayuth said the attack showed that Thailand “still has a person or a group of people with hostility to the nation operating actively”. There was a second blast on Tuesday, but it wasn’t deadly. The authorities are still waiting for lab-test results before confirming the type of bomb that was used to stage the attack.